U.S. District Court Judge William Alsup's 41-page ruling determined that the Java APIs in the case were functional and utilitarian components of Java, and therefore not protected. Oracle's lawsuit claimed that Google's Android software infringed patents and copyrights for Java that Oracle acquired when it bought Sun Microsystems in early 2010.

Alsup was careful to say that this ruling wasn't meant to apply to all Java APIs, just the ones in the case, but his decision nonetheless was applauded by some observers, who felt that if he ruled in Oracle's favor, it would set a bad precedent and inhibit new innovations in programming.

Now Oracle will have some time to regroup and mull over strategies for its appeal, said Edward Naughton, an intellectual-property lawyer with the Boston firm Brown Rudnick, in an interview Friday. "The appeal process is an interesting one, because they get more time and are able to focus their arguments a little bit more on what the law should be, rather than what it currently is," Naughton said.

Appeals courts consider prior cases when making decisions, as Alsup did in his ruling, Naughton said. However, "they have a little bit more freedom to make rulings that embody policy decisions," he added.

To this end, "Oracle can talk about what the law ought to be, what principles should be applied to these facts," Naughton said. "But they will also have to take on why Alsup's description of the Java language may be a little bit of an oversimplification. They need to challenge the premise of Judge Alsup's analysis and show the situation is more complicated than how he described it."

But Alsup brought a unique quality to the case, revealing recently that he has a background in computer programming, which helped him understand the issues in the case. When Oracle goes to an appeals court, the person sitting on the bench may not have the same depth of knowledge as Alsup, making its attorneys' jobs potentially even more difficult.

"Alsup is more technical than your average judge," Naughton said.

However, "lawyers who deal with technology cases have to translate some technical things in ways nontechnical people can understand. That's the skill of good appellate lawyers."

Oracle's lawyers will likely "comb back" through the testimony in the original case in search of evidence that shows the Java APIs constitute "more than just methods of operation," he said.

In one sense, Alsup's ruling made Oracle's appeal easier, since the judge agreed that the APIs reflected creativity and originality on the part of their creators. "Now they can concentrate their fire and their arguments on the idea of functionality. That's what they'll do."

Overall, Oracle has a good chance in its appeal, Naughton said. "The cases where you don't have a good shot is where the case turns on the credibility of a witness, a 'he-said, she-said' situation. On a case like this, where it's based on a legal question, they have a fine shot on appeal."

Still, "they're going to have to contend with a thorough, well-written decision by a careful judge and that's not easy," Naughton added.

The ruling is so artfully rendered, in fact, that Oracle will have a tough time winning an appeal, according to Tyler Ochoa, an intellectual-property law professor at the Santa Clara University School of Law.

"This is by far the most careful and well-written opinion on software copyright I've ever read," Ochoa said via email. "I will be astonished if it is not upheld on appeal."

Alsup's ruling is similar to one made by an appeals court in the mid-1990s, which found "that the menu command structure of [the software program] Lotus 1-2-3 was original and creative, but that it was not copyrightable because it was also a method of operation," Ochoa added. "Although that was something of a controversial ruling at the time, it has widely come to be accepted law, and I would be astonished if the Court of Appeals or the Supreme Court would take issue with it now."

Moreover, Oracle will not only have to convince the appeals court Alsup was wrong, but also "persuade a jury on retrial that the use was not a fair use" under copyright law, Ochoa added. "Oracle can continue pouring money down this sinkhole if it wants to, but it would be well-advised to concede defeat now."

Prior to Alsup's ruling Thursday, a jury cleared Google of patent infringement in the case.

(James Niccolai in San Francisco contributed reporting to this story.)